1. Field of the Invention
The present invention relates to an anhydrous ammonia applicator and, more particularly, to an anhydrous ammonia applicator designed for pumping large amounts of anhydrous ammonia into the soil over a wide area.
2. Description of the Prior Art
It is well-known in the art to apply anhydrous ammonia to the soil to increase the nitrogen content thereof. For grasses such as corn, nitrogen application is required in many instances to achieve the full potential yield of the crop.
Anhydrous ammonia application systems typically include a high torque vehicle, such as a tractor, which pulls a tool bar or similar implement for cutting into the soil. Pulled behind the tool bar is a small trailer onto which is secured a small gas-tight tank. Hosing is routed forward from the tank to the tool bar and then to knives located on the tool bar. The knives are used to inject the anhydrous ammonia below the surface of the soil.
If the ambient temperature is sufficiently high, some of the anhydrous ammonia within the tank vaporizes and generates pressure within the tank. This pressure is used to force the vaporized anhydrous ammonia through the hoses to the knives. After the anhydrous ammonia has been injected into soil, the anhydrous ammonia is covered with additional soil to reduce the amount of anhydrous ammonia lost to the atmosphere.
While this prior art technique has been used for many years to inject anhydrous ammonia into the soil, this technique has several drawbacks. One drawback is that the system relies on the ambient temperature being sufficiently high to pressurize the anhydrous ammonia. If the ambient temperature is too low, the pressure generated in the tank will be too low to force the anhydrous ammonia through the hoses and into the soil. Accordingly, this system cannot be used during a large portion of the fall/winter application time.
An additional drawback is the small capacity tanks used in the prior art to apply the anhydrous ammonia. Because of the small capacity of these tanks, the pulling vehicle must stop frequently to have the empty tank replaced with a full tank. The prior art typically uses a pick-up truck, or similar vehicle, to pull the full tanks of anhydrous ammonia from a large stationary tank at a remote location to the applicator vehicle. This scenario often causes a potentially dangerous situation if a plurality of filled tanks are pulled behind a truck or if the tank were to become detached from the truck during transit. Additionally, the small capacity of the tanks requires the pick-up to make numerous trips back and forth, thereby increasing the time on the road and the potential hazards naturally associated with pulling farm style trailers on public highways.
Still another drawback associated with the prior art system of anhydrous ammonia application is the problem associated with applying an additional material such as a nitrogen stabilizer. Since the prior art system is not specifically designed for a plurality of application materials, the secondary materials, such as a nitrogen stabilizer, are typically combined with the anhydrous ammonia before being placed in the small tanks. While combining the materials allows both materials to be dispensed from a single tank, the corrosive nature of the nitrogen stabilizer substantially reduces the useful life span of the tanks. As the tanks become prematurely pitted and rusted, costs are increased since the tanks must be replaced more frequently.
Yet another problem associated with the prior art system for anhydrous ammonia application is the difficulty associated with monitoring the application process to quickly discover and address potentially harmful leaks of anhydrous ammonia. When applying anhydrous ammonia to the soil, the vehicle is being driven forward, while the material is applied behind the vehicle. It is not possible for the operator to simultaneously monitor both the direction of the vehicle's travel and the application of the anhydrous ammonia to the soil.
Accordingly, if a leak were to occur during the application of the anhydrous ammonia, it may be several minutes before the operator turns around and notices the problem. Such a delay could result in a large loss of relatively expensive anhydrous ammonia. Additionally, if it is unclear when the leak began, it is difficult to determine how much of the soil must be reinjected with anhydrous ammonia. Most importantly, loss of a significant amount of anhydrous ammonia into the atmosphere could result in a harmful, or even potentially life threatening, situation if the anhydrous ammonia were to be inhaled by the operator or persons standing nearby during the application process.
Still another drawback associated with the prior art system is the large amount of soil compaction it creates. Prior art systems use tractors with relatively narrow tires to apply anhydrous ammonia. Narrow tires leave a relatively large imprint in the soil making it more difficult to work the soil for cultivation, planting etc. Additionally, the relatively narrow track of the pulling vehicle limits the use of the system in moist or soggy soil conditions. More importantly, since the prior art system pulls the anhydrous ammonia tank behind the toolbar, the tank packs the soil down after the toolbar has just worked the soil. Regardless of the amount of anhydrous ammonia in the tank, as long as the tank is pulled along the ground behind the toolbar, some undesirable compaction of the soil will occur.
Another drawback of the prior art application system is its inefficiency. As noted above, tractors used to apply anhydrous ammonia have relatively narrow tires which limits the pulling force and the size of the tool bar which can be pulled. Since tractors are typically used for numerous applications around the farm, many of which require the tractor to navigate within the confines of rows of sprouted plants, use of wider tires is typically undesirable. In addition to the prior art being limited to the size of toolbar, and accordingly, the area of ground that can be covered, the small capacity of the prior art anhydrous ammonia tanks also limits the amount of material which can be applied before the tractor must stop and switch tanks. All of these factor coact to decrease the efficiency of prior art systems for anhydrous ammonia application.
The difficulties encountered hereinabove are sought to be eliminated by the present invention.